The invention relates to an apparatus for reproducing magnetic signals recorded in tracks on a magnetic tape, hereinafter referred to as a tape player or tape recorder, comprising: a frame with a front panel; a magnetic read head with a magnetic core having pole pieces between which a read gap is formed for scanning the magnetic signals on the magnetic tape; as well as an azimuth-angle correction device for correcting an incorrect azimuth-angle position of the read gap relative to a track on the magnetic tape and more particularly to such a device comprising a pivoting plate, which carries the magnetic head and which is pivotable relative to the frame for influencing the azimuth-angle position of the read gap by pivoting the pivoting plate, and a movable pivoting member, which cooperates with the pivoting plate for pivoting the pivoting plate when the member is moved.
When reproducing magnetic signals recorded in tracks on a magnetic tape it is essential that during reproduction the correct angular position of the read gap of the read head relative to the selected track is maintained. An incorrect angular position of the read head results in high frequencies of a signal recorded by means of a magnetic write head not being reproduced in an optimum manner. The write head also has a magnetic core with pole pieces between which a write gap is formed. The position of the write gap determines the orientation of the magnetic signals recorded on the magnetic tape. The write gap and read gap should therefore have the same angular position, as closely as possible.
A deviation of only a few minutes of arc from the correct angular position of the read gap may lead to the high-frequency reproduction of an audio signal being deteriorated by a few KHz. This problem may inter alia occur when the signals have been recorded on the magnetic tape with an apparatus other than that with which the magnetic tape is played back. In order to reduce the resulting interchangeability problems, it is therefore necessary that different apparatuses have a corresponding adjustment of the neutral position of the two magnetic heads.
It is obvious that in practice the accuracy of this neutral adjustment cannot surpass what is feasible and efficient in production. However, even in the case of correctly adjusted apparatus it happens that the reproduction of signals which have been recorded by means of another apparatus, for example the reproduction of commercially available prerecorded compact cassettes, the so-called music cassettes, is not optimum, because either the neutral adjustment of the write gap of the write head used during recording or the adjustment of the read gap of the read head of the tape player is not optimum, for example because as a result of shocks or mistreatment of the write head, the read head or both heads does or do not have the correct position. In such a case a substantial improvement in reproduction quality can be obtained by slightly readjusting the read head of the tape player, so as to ensure that the read gap of the read head is, as much as possible, parallel to the write gap of the write head used for recording the tracks and thus to the orientation of the tracks on the magnetic tape. This improved reproduction especially manifests itself in an audible improvement of the treble reproduction.
In several known tape players the read head, which serves for reproducing the recorded magnetic signals, is mounted on the frame so as to be adjustable. The read head is secured to a plate which is supported by the frame in such a way that the azimuth angle can be changed with the aid of a set screw. During manufacture this set screw enables the neutral position of the read gap to be adjusted within the required tolerance range with the aid of a screwdriver. It is evident that such an azimuth-angle correction device is less suitable to be operated by a user during the reproduction of music, because in this situation the player is connected to the mains voltage and, moreover, the relevant read head is covered by the front panel of the apparatus. Especially in the case of Compact-Cassette recorders provided with a hinged cassette holder in which the cassette is inserted before it is swung into an operating position, there is not much room near the read head.